A100150 Structured snub cubic numbers.
1, 24, 107, 288, 605, 1096, 1799, 2752, 3993, 5560, 7491, 9824, 12597, 15848, 19615, 23936, 28849, 34392, 40603, 47520, 55181, 63624, 72887, 83008, 94025, 105976, 118899, 132832, 147813, 163880, 181071, 199424, 218977, 239768, 261835, 285216, 309949, 336072
Offset: 1
Links
- Vincenzo Librandi, Table of n, a(n) for n = 1..5000
- Index entries for linear recurrences with constant coefficients, signature (4,-6,4,-1).
Crossrefs
Programs
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Magma
[(1/6)*(38*n^3-48*n^2+16*n): n in [1..40]]; // Vincenzo Librandi, Jul 19 2011
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Mathematica
LinearRecurrence[{4,-6,4,-1},{1,24,107,288},40] (* Harvey P. Dale, Sep 17 2020 *)
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PARI
a(n)=n*(38*n^2-48*n+16)/6 \\ Charles R Greathouse IV, Jul 18 2011
Formula
a(n) = (1/6)*(38*n^3 - 48*n^2 + 16*n).
G.f.: x*(1 + 20*x + 17*x^2)/(1-x)^4. - Colin Barker, Jan 19 2012
From Elmo R. Oliveira, Aug 05 2025: (Start)
E.g.f.: exp(x)*x*(19*x^2 + 33*x + 3)/3.
a(n) = 4*a(n-1) - 6*a(n-2) + 4*a(n-3) - a(n-4) for n > 4. (End)
Extensions
Deleted extra +16 in formula, corrected by Craig Ferguson, Jul 18 2011